Severance Package

Hi:

I have recently been laid off, the company gave me a severance package, which indicated a lump sum of $xxxx will be paid to me after 7 days I signed the paper. I have couple of questions:

(1) In my offer letter, the company has promised 10% bonus per year according to company performance, but I have never got any bonus. Can I ask them to pay the bonus before I sign the severance package?
(2) What else I should pay attention in serverance package?

Thanks for your advice